1. Field
This invention relates to compounds for use in organic light emitting diodes, such as for host materials.
2. Description of the Related Art
White organic light emitting devices (WOLEDs) have attracted much attention and been intensively studied due to their potential applications as backlight sources, full color displays, and general lighting. Among various device configurations to produce white light, a single-emissive-layer device employing phosphorescent materials in combination with proper host materials is desirable. Some advantages of such a device may include reduced overall cost, increased quantum efficiency, and easier fabrication. Since phosphorescent emitters can harvest both singlet and triplet excitons, use of phosphorescent emitters in WOLEDs may lead to the potential of achieving 100% internal quantum efficiency. Adding host materials may also reduce concentration quenching of the emissive materials and further increase the efficiency. In addition, adding host materials can reduce the required amount of expensive emissive material, and the fabrication of a single layer device is easier and more cost effective than a multiple layer device. As a result, the single-emissive-layer device with phosphorescent and host materials can lower the overall cost of fabricating the WOLEDs.